Small Block Chevy V8 Swap

It’s been a couple of weeks since NMCA’s fun, three-day drag race and autocross event in Fontana, California, where I muscled my big ’65 Chevelle around a cascade of orange cones in a tight parking-lot course. In most autocross courses, it’s possible to be very quick with mediocre horsepower, as long as you’ve got a small, light vehicle that can negotiate the layout quickly and stay away from the cones. That’s exactly what we hope to build with Project Sten. The truck is light at only 2,600 pounds, but the four-banger falls short of mediocre and doesn’t have the power to compete even on a short parking-lot course, so that makes the small block Chevy a natural swap. The ideal conversion would be an all-aluminum LS motor, and perhaps there’s one in our future, but for now we’ll stick with our affordable, if somewhat dated, TPI small block Chevy.

This small block Chevy swap has been done a thousand times, which means it’s a really good idea. We’re somewhat limited by California smog laws that require an emissions-legal engine, so the TPI motor we outlined last month is not necessarily going to roll the Sten into the 10s in the quarter-mile. But it should produce excellent torque and enough power to make it fun. In addition to dishing out the details involved with stuffing the engine between the fenders, we’ll touch on the transmission and clutch pieces, which we’ll cover more extensively in an upcoming issue. We couldn’t find a used, V8, third-gen Camaro T5 five-speed trans we could trust, so instead we traded a few baubles for a ’90 Camaro, V6 trans that we sent to Modern Driveline in Utah for V8 ratios and a rebuild. Though known more for its work with Fox-body Mustang T5s, the company works on GM boxes as well. The stupid-deep V6 gears were removed and replaced with Tremec 2.95:1 First-gear pieces. We have plans to update the rearend, but we’ll save that for a later story as well.

For now, the big push is to get the small block Chevy engine in the truck. Our first step was to contact Mike Knell, whom we’ve mentioned in previous stories. His company, Jaguars That Run (JTR), published an extensive, 220-plus-page S10 V8 swap manual with tons of very specific information. The book is easily worth 10 times what he charges in terms of information that will save you time, grief, and skinned knuckles. If you are considering attempting this swap, buy the book first. We’ll hit the high spots of what’s needed to get the engine in the truck, but we don’t have the space to cover all the details fleshed out in the book. But enough talk—let’s get into spinning wrenches.